Talk:Twin Quasar

WikiProject class rating
This article was automatically assessed because at least one WikiProject had rated the article as stub, and the rating on other projects was brought up to Stub class. BetacommandBot 10:05, 10 November 2007 (UTC)

Do not duplicate MECO article here!
This article seems to contain not so much information on the Twin Quasar but on MECO. I am going to delete large part of the article, just having a link to MECO article ought to be enough. To be honest, to me it looks like an attempt to "enhance the image" of MECO theory. I respect your interest in whatever theories you are interested, but it's not a good reason to copy-paste MECO description in unrelated articles. 89.103.91.47 (talk) 08:29, 21 June 2008 (UTC)
 * I removed the duplicated material and inlined a couple of links. Tim Shuba (talk) 17:46, 19 October 2008 (UTC)


 * You could just have restored the original explaination on _why_ the MECO claim was made for the Twin Quasar. 76.66.198.46 (talk) 06:42, 14 November 2008 (UTC)

Twin Quasar v Twin QSO
See this discussion at WT:ASTRO about the recent renaming and revision to the notation format used in this article. 76.66.201.179 (talk) 06:35, 17 March 2009 (UTC)
 * Discussion was archived at Wikipedia_talk:WikiProject_Astronomical_objects/Archive_12#Twin_Quasar. 70.29.213.241 (talk) 08:45, 16 April 2009 (UTC)

Distance
Hello, There are 2 figures for the distance of this: 7.8 Gy and 8.7 Gy. Which one is the good one? Yann (talk) 18:04, 24 July 2009 (UTC)

In the right table you state that the QSO is at 7.8 billion l.y, but in the text it is close to 14 billion l.y (what confirm HST and NASA). So the text must be adapted. The comment released on HST or NASA website is clear: the QSO is located close to 14 billion l.y while the galaxy G1 is some 4 billion l.y away.

"These cosmic doppelgangers make up a double quasar known as QSO 0957+561, also known as the "Twin Quasar," which lies just under 14 billion light-years from Earth. Quasars are the intensely powerful centers of distant galaxies. So, why are we seeing this quasar twice? Some 4 billion light-years from Earth — and directly in our line of sight — is the huge galaxy YGKOW G1."

Mass of lensing galaxy YGKOW G1
It is highly frustrating how difficult it is to find the mass of the lensing galaxy in this foundational system. (For example, searching Google for "YGKOW G1" "lensing mass" etc. etc. etc. is a very very very long exercise in frustration.) Finally finding https://arxiv.org/pdf/astro-ph/9608117 = AJ 113, 521 (1997), it appears from that paper that the lensing mass here is in the vicinity of (3.8 +- 1.2) x 10^14 M_solar (combining numbers from that paper which has a central value of 3.9 x 10^14 M_solar, and a previous paper which that paper cites which has a central value of 3.7 x 10^14 M_solar). Assuming that I am not confused and that number is reasonably correct, and there are no very different and more recent estimates, having that estimate of (3.8 +- 1.2) x 10^14 M_solar for the lensing mass of the system, along with a reference for it to https://arxiv.org/pdf/astro-ph/9608117 and/or AJ 113, 521 (1997) I feel would be a very welcome addition to the page (although I don't feel I am expert enough in this lensing system to make the addition to the page myself).

External links modified (January 2018)
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